The study showed a significantly higher rate of neurologic injury in the immobilized group.
In 2012, Dr. Hauswald released another article on the biomechanics and pathophysiology of spinal injures that challenged existing spinal immobilization theory. In his article Dr. Hauswald asserts that most spinal injuries are biomechanically stable, that the majority of those few patients with unstable spinal injuries will already have spinal cord damage as a result of the forces imparted during the traumatic event, and that pre-hospital immobilization will not affect either patient's outcome. If true, it means that cord and neurological injury can only be caused by a second traumatic event where new force is applied to the injured area, and movement within the patient's normal range of motion is safe.
Definitive proof of Hauswald's biomechanical theory is hard to come by without taking a gigantic a leap of faith, ceasing all current spinal immobilization practices, and gathering new data. If spine immobilization and subsequent evacuation were safe and inexpensive, we would continue to immobilize potentially spine-injured patients as we have always done. Unfortunately, this is not the case. Research over the past decade clearly demonstrates that full spinal immobilization:
- requires a litter evacuation and transport. In a remote environment, the evacuation often puts both patients and rescuers at risk.
- that includes the use of hard cervical collars raises intracranial pressure, even in uninjured subjects.
- may cause respiratory compromise in some patients due to positioning, tightness and location of chest straps, or the use of cervical collars.
- causes pain.
- causes potentially devastating pressure sores if the litter is not extremely well-padded.
Here's what else we know (or think we know):
- The 2000 National Emergency X-Radiography Utilization Study (NEXUS) and the 2001 Canadian Cervical Spine Rule (CCR) produced the two most widely used algorithms used in EDs to identify patients who do not require spinal imaging. Use of the NEXUS and CCR criteria for the field clearance of potentially unstable spine injuries is both safe and effective. Meta-analysis on clearance of the asymptomatic cervical spine showed the NEXUS & CCR negative predictive value is 99.6%, it's positive predictive value is 3.7%; the overwhelming majority (96.3%) of patients who fail the exams do not have an unstable spine injury. The State of Maine uses a Nexus-based protocol includes spine pain and paraspinal tenderness. Most wilderness medicine providers teach a focused spine assessment based on the NEXUS algorithm; the algorithm is modified to include spine pain and applies to the entire spine (the original NEXUS low risk criteria did not include spine pain and was only applied to the cervical spine).
- A very low percentage of awake, alert, reliable, and ambulatory patients have an unstable spine or cord injury.
- Neurologic deficit-motor or sensory impairment not attributable to an extremity injury-indicates a potential cord injury.
- The use of a full-body vacuum split offers the best spinal support for non-ambulatory spine-injured patients.
- The use of cervical collars is controversial:
- Even the best cervical collars do not fully immobilize a patient's spine.
- Live subject and cadaver studies show that there is less spine movement during an extrication when a cervical collar is applied and alert, reliable patients are permitted to extract themselves from the situation than when trained rescuers perform the extrication.
- Cervical collars increase ICP even in uninjured subjects.
- Cervical collars may restrict access to the patient's airway.
- The effectiveness of spine immobilization in preventing further neurological injury is uncertain.
After thorough search of the existing research an expert panel formed by the Wilderness Medical Society proposed a new algorithm that subjectively reduced the threshold for pain and tenderness and added range of motion tests for the cervical and lumbar spine. The algorithm was first published in the fall 2013 and updated late 2014; to date there is no data regarding the safety of the new algorithm.
What does this mean?
- Allow reliable patients to extricate themselves; they will do a better job by themselves or with rescuer assistance than if rescuers apply current immobilization strategies and carry out the extrication for them.
- Consider using a cervical collar while lifting and moving voice-responsive, pain-responsive, and unresponsive patients into a litter for transport and removing the collar after the patient's body is fully supported (not fully immobilized) in the litter. Consider leaving the collar in place if litter transport is unduly rough and lateral head support is not available or in place. Or, consider not using a cervical collar at all.
- Transport non-ambulatory patients who fail a focused spine assessment based on the NEXUS or CCR criteria in a litter or stretcher using a vacuum splint. If a vacuum splint is unavailable, use thick, soft, materials for padding under the patient and around their head and neck to support their spine during the evacuation. Spinal immobilization is not necessary.
- Consider using the "Spine as a Long Bone" principle to permit selective spinal protection in high-risk areas and prevent some iatrogenic injuries during prolonged transport.
- Critical system problems take priority over potential spine injuries. For example:
- Package head-injured patients on their side in the recovery position to support airway management.
- Loosen chest straps if they compromise the patient's breathing.
- Raise/support the patient's chest within a litter or stretcher to ease their breathing.
- When conditions warrant and in consultation with the patient, consider using a padded cervical collar or thoracic/lumbar support if it's application reduces spine pain in the ambulatory and reliable patient with ± neurological deficit who fails a NEXUS- or CCR-based focused spine assessment.
- Consider transporting non-ambulatory patients in position of comfort with spinal support who do not meet the NEXUS or CCR criteria.
- Urban and rural EMS and wilderness rescue personnel and agencies are changing their protocols based on the current research and amassing new data. The new data will ideally help identify effective practices for pre-hospital spine management and may dramatically change current protocols in coming years....